The general concept of pressure thrust is known in the fluid dynamics design art, to include airfoils, aircraft and submarines. The phenomenon uses energy of an airflow rushing past an airfoil or a surface, such as but not limited to a fuselage, to generate an area high pressure which exerts a force on the airfoil or the surface which pushes the airfoil or the surface in a substantially forward direction. In at least one example, the airflow is channeled against the airfoil to increase the pressure near the airfoil which increases the force pushing the airfoil in a substantially forward direction.
In the 1940s and 1950s the Griffith Aerofoil was developed. Researchers focused on very thick aerofoils, for use on span-loaded flying-wing transport and they proved a meaningful decrease in total power required for those designs. Fabio Goldschmied with help from Denis Bushnell at NASA uncovered and verified the pressure thrust phenomenon.
Moreover, the Coanda Effect is another concept that is known in the fluid dynamics design art. The Coanda Effect describes the phenomenon of how a fluid flow behaves when it is substantially adjacent a surface. Specifically, the Coanda Effect describes the tendency of a fluid flow to stay attached to a surface even if the surface curves away from an initial path of the fluid flow.
The general concept of airfoils is also known in the fluid dynamics design art. Specifically, it is known that convex surfaces facilitate accelerating a fluid flow that is adjacent the convex surface as the surface travels through a fluid medium. Conversely, a concave surface facilitates decreasing the speed of a fluid flow that is adjacent the concave surface as the surface travels through the fluid medium. This is the general concept behind pressure thrust, wherein a concave surface facilitates decreasing the airflow creating an area of above-ambient pressure. Aerodynamic lift is created when an airfoil, with an upper surface that may be convex, creates lower-than-ambient pressure above the upper surface. As a result, the pressure differential between the relatively high pressure area under the airfoil and the relatively low pressure area above the airfoil facilitates exerting a force on the airfoil that pushes, or lifts, the airfoil upwards.
The general concept of shockwaves is also known in the fluid dynamics design art. Specifically, shockwaves are produced during the transition of an object or a flow of fluid traveling at subsonic speeds to supersonic speeds, or vice versa. During transonic speeds of an aircraft, the airflow may have a velocity that is accelerated by surfaces such as, but not limited to airfoils and fuselages of the aircraft. As a result, when an aircraft is traveling at transonic speeds that are substantially below Mach 1.0, at least a portion of the airflow may be accelerated to speeds greater than Mach 1.0. As a result, a shockwave is produced. Moreover, when the velocity of the supersonic airflow is reduced to a velocity that is subsonic, a shockwave is also produced. This shockwave includes a high pressure area positioned substantially near the surface of the aircraft.
Boundary Layer Control (“BLC”) methods are generally known in the aerodynamic arts. BLC methods are exploitable for increasing lift coefficients of airfoils, among other goals. Typically, BLC methods are exploited to control the boundary layer of air on the main wing of an aircraft. BLC methods applied to the main wing of an aircraft reduce drag thereon and increase the maximum the usable angle of attack and maximum attainable lift coefficient, which increases performance.